Knife-marker.



W. C. FARN'UM.

KNIFE MARKER.

APPLICATION. rmEn OCT. 3, 1911.

Patented May 6, 1919.

a SHEETS-SHEET 1.

ufifiiorne y.

W. 0. FABNUM.

KN IFE MARKER. APPHCATIO N FILED' OCT. 3. 1911.

1,302,646. Patented May-6,1919.

3 SHEETS-$HEET 2. 6.

Inventor.-

TENT onto.

WILLIAM C. FARNUM, OF WINCHENDON, MASSACHUSETTS, ASSIGNOB TO WILLIAM M.

WHITNEY, OF WINCHE'NDON, MASSACHUSETTS.

KNIFE-MARKER.

Specification of Letters Patent.

Patented May 6, rain.

Application filed October a, 191v. Serial No. 194,625.

To all whom it may concern:

Be it known that I, WILLIAM G. FARNUM, a citizen of the United States, residing at VVinchendon, county of Worcester, and State of Massachusetts, have invented an Improvement in Knife-Markers, of which the following description, in connection with the accompanying drawings, is a specification, like characters on the drawings representing like parts.

The invention hereinafter described relates to instruments for laying out the cutting edges of knives of cutters for shaping moldings and other articles.

Such cutters usually comprise a body having a plurality of knives secured thereto and adapted to act successively on the work.

It is desirable to have the knives oblique to the plane of the Work when in active engagement therewith. Consequently, the cutter body is usually made square presenting flat faces on which the knives are secured in planes tangent to a circle concentric with the axis of rotation of the cutter.

If each knife were on a radius of the cutter and perpendicular to the plane of the molding when making its greatest depth of cut, the cutting edge of the knife could be formed toexactly conform to the contour of the molding; but when the knife is oblique to the molding, points on the cutting edge will cut deeper into the work than when the knife is perpendicular to the molding. As a result, in laying out the cutting edge of the knife, it is necessary to form the same to compensate for the obliquity of the knife with respect to the molding.

Heretofore, instruments have been de signed intended for this purpose, but they are unsatisfactory for a number of reasons. Among others, they are difiicult to use, require too much time, and cannot be relied upon to do accurate work. g p

The present invention provides a simple and effective instrument which overcomes the aforesaid objections.

The character of the invention may be best understood by reference to the folk lowing description of one good form there of shown in the accompanying drawings, wherein I Figure 1 is a side elevation of a molding cutter and a cross section of the piece of molding adjacent thereto;

Fig. 2 is an end elevation of the cutter and a side view of the molding shown in Fig. 1; I Fig. 3 is a viewshowing the relation of the cutting edge of a knife to the molding when perpendicular thereto;

Fig. 1 is an end view of the knife, shown in. oblique position in full. lines, and in perpendicular position in dotted lines;

Fig. 5 is a diagram showing the relation of the pattern and knife blank supports and different positionsof the tracer means and its carrier;

Fig. 6 is a plan of the instrument;

Fig. 7 is a front elevation thereof;

Fig. 8 is an end elevation looking toward the left of Fig. 7

Fig. 9 is an end elevation looking toward the right of Fig. 7

Fig. 10 is a detail section taken on line 10 10 of Fig. 8;

Fig.11 isa detail section taken on line 11 of Fig. 8; and

Fig. 12 is a detail section taken on line 12-12 of Fig. 8. i

Referring to the drawings and more particularly to Figs. 1 and 2, 1 designates a shaft n which a usual molding cutter is mounted comprising a square body 3 having apair of knives 5 secured by screw bolts 7 to opposed fiat faces of said body. Each of said knives has a bevel cutting edge .9 formed with a contour suitable to produce the contour 11 on a piece of molding 13..

The knives are tangent to a circle 15 concentric with the axis of rotation 17 of the cutter, so that when each knife is rotated to a position to make its greatest depth of out the molding, it is oblique to the plane thereof as mdlcated by the posltion of the knife shown in dotted lines in Fig. 2.

Fig. 3 shows one ofthe knives having an edge contour which will produce the required contour for the molding when the knife is oblique thereto, as shown in Fig. 1; but when the knife is rocked to a position perpendicular to the molding as represented in Fig. 3 and as shown in dotted lines in Fig. 4, certain points on the edge contour of the knife will move upaway from the contour of the molding. For example, the point a of the edge contour of the knife engages the point a on the molding when the knife isobliqu'e thereto, but when the the knife may be quickly and accurately laid out suitable to produce the molding contour required and compensate for the obliquity of the knife with respect to the molding in acting thereon.

This instrument comprises a base 19 having a support thereon, in the present instance of the invention, in the form of a post 21 rectangular in cross section and carrying a horizontal bar 23 at the upper end thereofsecured to said post substantially midway between the ends of said bar by aset screw 25 (Figs. (5 and 8) adapted to clamp a split portion 26 of said post tightly to said bar.

The pattern which it is desired to reproduce may be of any selected design drawn on paper or other suitable material. The pattern 27 (Fig. 6) selected herein is of sheet metal having an edge contour 29 in the form which it is desired to reproduce.

Suitable means is provided to support the pattern, in the present instance of the in- ,vention, in the form of a table 31 mounted and adapted to rock on the bar .23, referred To allow this rocking movement, the table may have a long arm 33 (Fig. 6) and a' short arm 35 projecting rearward therefrom and apertured to receive said bar. The

table may be confined against movement in the direction of the axis of said bar by the engagement of the long arm with the post and by the engagement of the short arm 35 with a washer 41 held by a screw 43 in one end of said bar.

Suitable means is provided tending to cause the table to rock upward about said bar. To accomplish this, in the present instance of the invention, a helical spring 45 (Figs. 8 and 9) is provided adjacent the post 21 having its lower end anchored to apin 47 in said post, and its upper end connected to a pin 49 (Fig. 6) secured to an end of the long arm 33 projecting rearward from the bar 23.

To limit the rocking movement of the table, its long arm may have alug 51 thereon with ends adapted-to engage-the top 53 of the post 21.

The construction described is such that the spring will tend to rock the table upward until limited by the engagement ofone end of said lug with the top of said post, and the table may be pressed downward. againstthe resistance of said spring until. limited by the engagement ofthe other end. of said lug with the top of said post.

To relieve the table from wear, a plate 55 of tin or other suitable material may be mounted thereon and the pattern may be mounted on said plate. To secure the plate to the table, a. suitable clamp may be provided, in the present instance of the invention, in the form of a binding strip 57 secured to hooks 59 extending around opposed edges of the table and engaging the under side thereof as represented in Fig. 11. The binding strip may have its edges 61 curled upward about said hooks to grip the same.

To secure the pattern to the table, a suitable clamp may be provided, in the present instance of the invention, in the form of a bar 63 extending across the table over the pattern and having hooks 65 at the ends thereof projecting down around the edges of the table and connected by a bar 67 beneath the table. Binding screws 69 may be threaded into said hooks and have ends adapted to bear against the under edge of the table, so that when tightened they will react against said edge and draw the bar 63 downward and press and hold the pattern securely onto the table. These binding screws may be readily loosened to release the pressure on the pattern and permit the removal thereof from the table.

The article selected herein to have a pattern laid out thereon is a knife, such as shown in Figs. 1, 2 and 3, of a molding cutter. A knife blank 71 (Fig. 6) is selected of approximately the size required, with a margin at one end thereof which may be ground down to the knife edge contour after the latter is marked thereon.

The instrument is provided with suitable means to support the knife blank in proper position to have its edge contour laid out thereon. In the present instance of the invention, this support comprises a table 73 fast on a bracket 7 5 adapted to be secured to the post 21, referred to. To accomplish this, the bracket may have an arm 77 (Fig. 10 provided with a shallow recess 79 having a bottom adapted to be pressed against one side of the square post and ends adapted to engage portions of adjacent sides of said post. To press said recess against said post, a clamp plate 81 is provided having a notch 83 adjacent one end thereof adapted to fit over a corner of the post opposite the side engaged by said recess. The opposite end of said clamp plate is loosely mounted on a pin 85 in an arm 87 integral with said bracket. The clamp plate is adjustably scoured to said arm by a thumb screw 89 entered through a hole in said plate and threaded into a tapped hole in said arm.

The construction is such, that the bracket may be laterally presented to the post with the recess 7 9 fitting one side therof. Then the thumb screw 89 is tightened to press the clamp plate 81 against the opposite side of Then the table and its bracket may be with drawn laterally from the post. If it is desired to adjust the table vertically along the post, the thumb screw is released slightly but not suliicientlyto permit the clamp plate to escape from the corner of the post. Then the table is moved vertically to the position desired and the thumb screw is tightened to secure the tablein its selected position.

Fmitable means may be provided to secure the knife blank on the table. In the present instance of the invention this means comprises an angle bar 91 adapted to be superposed on the knife blank and be held-by screws 93 which may be threaded into selected holes of a plurality of holes 95 tapped into the table at regular intervals. The coin struction is such, that knife blanks of different sizes may be accommodated and positioned as required on the table.

The instrument is provided with suitable tracer means governed by the patternfor laying out the required edge contour of a knife for reproducing said pattern. In the present instance of the invention, thismeans comprises a pattern tracer or pin 97 (Figs. 7 and 8) and a knife marker or pin 99 (Figs. 7 and 9) mounted on a carrier for causing said tracer and marker to move parallel to theraxis of the bar 23. This carrier, in the present exemplification of the invention, comprises a rod 101 secured by set screws 102 to said pins and rotatively mounted in the free end of a frame comprising a forearm 103 ha-vingsplit portions 104 forming bearings for said rod, the friction thereof bein varied b screws 104: and 1% ada ated to draw said split portions toward one another. The forearm 103 is connected. by a hinge 103 with an upper arm 105 having bearings 107 adapted to rock and slide along the bar 23. ()ne of these bearings isat one side of the post and the other bearing is at the opposite side of the post, and the move ment of the carrier in the direction of the axis of said bar is limited by the cugagen'lent ofone of said bearings with the arms 33 and 35 of the pattern table. The friction of said hearings on said bar may be varied by screws 109 (Figs. 6 and 9) adapted to draw split portions 111 of saidbearing toward each other.

The axis of the bar 23 corresponds to the axis of rotation of a cutter; the distance between the pattern edge 29 and the axis of said bar corresponds to the radial distance of the cutting edge of the knife from the axis of rotation of the cutter; and the distance of the upper surface of the knife blank from the axis of said bar corresponds to the distance of the plane of a knife from the axis of rotation of the cutter.

In use, a pattern, such, for example, as the pattern 27 is clamped onto the table with its edge 29 a distance from the axis of the bar 23 determining the radial distance of the cutting edge of the knife from the axis of rotation of the cutter.

A knife blank, such, for example, as the blank 71 is secured onto the table (3 1n appropriate position, asuitable wear plate 73 being interposed between them, and the table is adjusted vertically along the post 21 until the upper surface of the knife blank is at a distance from the axis of said bar suitable to determine the distance of the plane of the knife'from the axis of rotation of the cutter. Then the pattern tracer 97 and the knife marker 99 together with the carrier are pressed downward and adjusted in the direction of theaxis of the bar until said tracer and marker engage, for example, the right hand ends of the pattern and knife blank respectively. The tracer and marker are relatively fixed and hence their points of engagementwith the pattern and blank will be in the same straight line. Inbringing the tracer and marker to this position, the pattern table is rocked downward against the resistance of its spring 4L5, which, as stated, tends constantly to urge the table upward. Then the tracer and marker and their carrier are moved to the left of Fig. 6. The

pattern tracer follows and is guided by the edge 29 of the pattern, and the knife marker concurrently follows along the sur face of and marks or lays out on the blank the contour of the knife edge required. Thus, the contour is laid out ontheblank easily and quickly with a single stroke of the marker.

down thereby as the distances of progressive points on the pattern edge vary from the axis of the guide bar.

In Fig. 5 isa diagrammatic illustration of three positions of the marker in laying out a patternon a blank, and the positions of the pattern support, and the forearm. and up per arm of the carrier, corresponding to said three positions. It will. be noted that the construction of the carrier is such that the tracer and markermay be moved together in a horizontal plane in following the contour of the pattern edge, while the pattern table is rocked to planes intersectingsaid plane with an obliquity varying according to the varying distancesv of points on the pattern edge contour from the axis of theb-ar 23.

While the instrument has been described more particularly in its use for laying out the cutting edges of a knife of a moldlng cutter, it will be understood that it is also adapted to lay out contours of other 21,1131: cles.

By my invention, an extremely simple instrument is provided whereby the contour required may be quickly, easily and accurately laid out.

It will be understood that the invention is not limited to the specific embodiment shown, but that various deviations may be made therefrom without departing from the spirit and scope of the appended claims.

What is claimed is 1. An instrument for laying out the cutting edges of knives of moldingcutters and the like, comprising, in combination, means for supporting a pattern, means for supporting a knife blank, relatively fixed tracers movable concurrently over the pat tern and knife blank respectively and means connecting said tracers.

2. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combinat on, means to support a pattern and a knife blank in intersecting planes, a tracer movable along the pattern, a marker concurrently movable over the knife blank, means connecting said tracer and marker, and means relatively to move said supports as said tracers are moved along said pattern and blank.

3. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a

guide member having an axis corresponding to the axis of rotation of a cutter, means to support a knifeblank in a plane tangent to a circle containing said axis, means to support a pattern with itscontour a distance from said axis and in a plane containing said axis, a tracermovable along said pattern contour, a marker movable along said knife blank concurrently therewith, and a carrier connected to said tracer and marker and mounted to rock on and slide along said guide member.

4. An instrument for vlaying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a guide member, means adapted to support a knife blank in p a plane offset from said member, means mounted to rock on said member and adapted to support a pattern, a

marker movable along the knife blank, a

tracer concurrently movable along the pattern for governing the movement of said marker and means connecting said marker and tracer.

5, An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a guide member, means adapted to support a knife blank, means mounted to rock on said guide member and adapted to support a pattern, a marker movable along the knife blank, a tracer connected to said marker and movable along the pattern, and means connecting said marker and tracer, said pattern support being rocked by said tracer as the latter moves along the pattern.

6. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a

7. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a guide member, means adapted to support a knife blank, means adapted to support a pattern, a pattern tracer, a knife marker, a carrier for said tracer and marker mounted to rock on said guide member, and means tending to rock said pattern support toward said tracer as the latter travels along the pattern.

8. An instrument for laying out the cut ting edges of knives of molding cutters and the like, comprising, in combination, a guide member, means adapted to support a knife blank, means adapted to support a pattern, one of said supporting means being movable relatively to the other, a pattern tracer, a knife marker, and an articulated carrier for said tracer and marker movably mounted on said guide member.

9. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a guide member, means adapted to support a knife blank, means adapted to support a pattern, one of said supporting means being movable relatively to the other, a pattern tracer, a knife marker, a carrier for said tracer and marker movably mounted on said guide member, and means to limit movements of said carrier.

10. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a uide member, means adapted to support a nifc blank, means adapted to support a pattern, a pattern tracer, a knife marker, and means connecting said tracer and marker to effect concurrent travel thereof along the pattern and knife blank, said guide member and knife blank sup ort being relatively adjustable to vary t e distance between them.

11. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a base, a post rising therefrom, a knife blank sup port, a clamp connected to said support for lateral presentation to and removal from said post, a pattern support mounted on said post, and tracer means adapted to move along the pattern and knife blank.

12. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a base, a post rising therefrom, a knife blank sup port, a clamp for said support having jaws for lateral presentation to said post, adjustable means to press said jaws against said post, a pattern support mounted on said post, a tracer movable along the pattern, and a marker concurrently movable along the knife blank.

13. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a standard, a guide member thereon, a support for a knife blank mounted on said standard, a support for a pattern mounted on said guide member, a tracer movable along the pattern, a marker movable along the knife blank, an articulated carrler mounted on said guide member, and a rod.

on said carrier secured to said tracer and marker. r

14. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a support for a knife blank, a support for a pattern, a guide member, an articulated carrier mounted to rock on and slide along said member, a rod, means frictionally to hold Gopies of this patent may be obtained for said rod in said carrier, and a pattern tracer and a knife marker secured to said rod.

15. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a support for a knife blank, a support for a pattern, a guide member, a carrier having bearings mounted to rock on and slide along said guide member, means to vary the frictional engagement of said bearings with said guide member, a rod on said carrier, and tracer means on said rod movable over the pattern and knife blank.

16. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a guide bar, a support for a pattern mounted to rock thereon, a support for a knife blank, a carrier mounted to rock on and slide along said bar, a pattern tracer and a knife marker on said carrier, and spring means tending to rock said pattern support toward said tracer.

17. An instrument for laying out the cutting edges of knives of molding cutters and the like, comprising, in combination, a standard, a guide bar thereon, a table for supporting a pattern mounted to rock on said bar, means tending to rock said table upwardly, a table for supporting a knife blank mounted on said standard, a carrier mounted to rock on and slide along said bar, and tracers on said carrier, one to follow along the pattern and the other to lay out a pattern on said blank.

In testimony whereof, I have signed my name to this specification.

WILLIAM C. FABNUM.

five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

